Cylinder head



Jan. 9, 1934. v MCPHERSON 1,942,439

CYLINDER HEAD Filed June 15, 1931 4 Sheets-Sheet 1 jwri/vraqvVa /y 1.WPera'a; i 0

Jan. 9, 1934. H. MCPHERSON CYLI NDER HEAD Filed June l5, 1931 4Sheets-Sheet 2 Jan. 9, 1934. H MCPHERSON 1,942,439

CYLINDER HEAD Filed June 15, 1931 4 Sheets-Sheet 3 Jan. 9, 1934. H. L.MCIPHERSON CYLINDER HEAD Filed June 15. 1931 4 Sheets-$heet 4 PatentedJan. 9, 1934 STATES PAT 23 Claims.

This invention relates to improvements in internal combustion enginesfor use in aircraft and more particularly to the construction of thecylinder heads of such engines together with enclosures for the valveactuating mechanism and associated accessories and parts, whereby moreeflicient cooling is accomplished.

Among the objects of the present invention are:

To provide protection for the more or less delicate parts associatedwith the heads of the cylinders;

To provide a head structure having a finished and pleasing appearance;

To provide a head structure which will smooth up the flow of airthereover and therearound;

To provide means for cooling such a head structure; and

To improve the details of construction of the head and its associatedparts.

These objects are accomplished:

By providing an elongated housing to completely enclose the cylinderhead and such associated parts as project therebeyond;

By shaping and streamlining the exterior of this housing so that it willoffer a minimum resistance to passage through the air; and

By so connecting the metal of the head and this outer housing as toaccomplish ready transfer of the heat of combustion from the head to theenclosing housing.

The means by which the foregoing and other objects are accomplished andthe'manner of their accomplishment will readily be understood from thefollowing specification on reference to the accompanying drawings, inwhich:

Fig. 1 is a sectional side elevation of the-head and housing taken onthe center line of the cylinder head;

Fig. 2 is a plan view of the housing for the head with a portion of suchhousing removed disclosing portions of the associated head partstherewithin;

Fig. 3 is a corresponding side elevation of the housing;

Figs. 4, 5 and 6 are transverse sections taken respectively on the linesIVIV; VV and VI-VI of Fig. 1;

Fig. '7 is a front end elevation of an engine structure enclosed by acowling with that portion of the structure in front of the line VII-VIIof Fig. 1, cut away; showing housings for the heads of a four cylinderengine projecting beyond the cowl surface, this fi ure being onapproximately one-half the scale of the preceding figures.

Referring now to the drawings in which the various parts are indicatedby numerals, 10 is the barrel or cylinder of an engine and 11 the headtherefor. These parts are shown secured together as by the threads 12,but may be integral to if it be so desired. 13 is the exhaust valve and14 the intake valve. 15 is the intake passageway, which leads rearwardlyfrom the intake valve and thence radially inward. Connection to the Vintake manifold or carburetor not being germane to this invention is notshown. 16, 17 is an exhaust passageway leading forwardly from theexhaust valve 13 to an exhaust manifold or ring 18 which is of annularform. The exhaust discharge pipe leading from this manifold not beinggermane is not shown. 19 is a fragmentary portion of the cowl in frontof this annular manifold, and 20 the cowl leading rearwardly therefrom.21, 22 are the valve stems of the exhaust and intake valves respectivelywhich stems project outward through the head 11. The valve 13 and itsstem 21 is disposed directly in front of the valve 14 and its stem 22.23 are the usual compression springs holding these valves against theirseat.

24 is a boss integral with the valve head and extending therefromsubstantially on the axial center line of the cylinder. Screwed intothis boss is a threaded post 25 the upper end of which is provided witha fork 26. Between the arms of the fork are disposed a rocker arm 27 foractuating the intake valve 14, a rocker arm 28 for actuating the exhaustvalve 13, and a master rocker arm 29 for actuating the two rocker arms27 and 28. These arms are pivotally mounted in common on a pin 30, whichmay be surrounded by a bushing 31 disposed through the arms of the fork26. One of the rocker arms as the arm 28 is an inverted U shape in crosssection and embraces the other arm 27. The master rocker arm 29 is alsoan inverted U shape in cross section and embraces both the arms 27 and28, the bottom of the U resting against the top of the arms 2'7 and 28when both valves are closed. The master rocker arm 29 is oscillated by adouble acting rod 32, the actuating mechanism for which rod notbeinggermane is not shown.

The passageway 15 is preferably transversely enlarged and provided witha central wall 33 having a hole 34 therethrough somewhat larger than therod 32 so that this rod may pass directly through the center of thepassageway without reduction of area thereof. If desired, this centralwall may be continued to form the guide boss through which the exhaustvalve stem 22 passes.

The exhaust and intake passageways, valve stems and actuating parts areall aligned parallel to the longitudinal axis of the engine.

Disposed over the valve stems and rocker arms is a housing which is intwo parts, a lower portion 35 and a cap 36. The lower portion 35 isintegral with the head 11 extending upward and inwardly thereabove. Inplan it; e housing is an elongated stream line structure with theforward end slightly in front of the cylinder and the rear end welltherebehind. Disposed transversely across within the housing are anumber of ribs one of which 37 is disposed immediately in the rear ofthe rod 32. This rib extends vertically downward to the bottom of thehousing and thence runs forwardly with and forming the bottom of thehousing until it meets the wall of the head 11. Another of these ribs 38extends in opposite directions from the boss 24 being integral with thisboss, with the head and with the housing. Disposed between the ribs 37and 28, and in front of the rib 38, are additional transverse ribs 39which are integral with the head and extend from such head to the sidewalls of the housing. These ribs serve the double purpose ofstrengthening the head and transferring heat therefrom to the walls ofthe housing. A hub or boss 40 extends forwardly from the forward end ofthe housing 35 to provide for the passageway 16. Lying along the top ofthis boss and coextensive in length therewith is a lug 41 which istapped out to receive a screw 42. The wall surrounding the passageway 17extends upwardly and rearwardly from the annular exihaust manifold 18,being welded thereto, and

surrounding an aperture corresponding to the passageway, and is providedwith a lug 43 through which a bolt 42 passes to secure the two parts ofthe passageway together. 44 is a gasket lying between these two parts ofthe passageway.

The housing cap 36 is shaped to complete the stream lining of the lowerportion 35 of the housing. This cap is preferably secured by screws 46which pass through lugs 4!? at each side of the cylinder head 11 and arescrewed into lugs 48 integral with and projecting inward from the cap.By loosening these screws the cap may be removed to permit inspection,oiling and adjustment of the various working parts lying within thehousing. 49 indicates a spark plug lying within the cowl.

In this structure the forward cowl or nose 19 terminates adjacent to butslightly in front of the annular exhaust manifold. The outer wall 50 ofthis manifold forms a rearward continuation of the nose and from theback of this manifold the cowl 20 extends rearwardly being cut awaybeneath the housing 35 where the head 11 protrudes.

' are protected against shock or weather and it is possible to make anextremely smooth structure for diverting the air past the engine. At thesame time it will be seen that the heat absorbed by the cylinder headfrom the hot gases in the combustion chamber is directly radiated wherethe cylinder head and housing blend into each other and elsewhere isconducted through integral metal fins or ribs from the head to thehousing, from the exterior surface of which housing it is radiated. Itwill further be seen that the air flow over this housing is smooth andsteady without pockets or partial vacuum so that swiftly flowing air isin direct contact with the entire outer surface of the housing whereby aminimum of radiating surface is required to cool the engine. The coolingis further augmented by the heat taken up by the air and gasolinemixture flowing through the intake passageway which is integral with thecombustion chamber and housing. The heat absorbed by the vaporization ofthe gasoline in this passageway is considerable.

The structures herein shown and described constitute preferredembodiments of the invention, but it is to be understood that otherforms might be adopted and changes made, all coming within the scope ofthe claims which follow:

Having described my invention, what I claim 1. A cowled aircraft enginehaving a plural ity of radial cylinders, said cowl being apertured ateach cylinder and the heads of the engine cylinders extending throughsaid apertures; each cylinder head having parts projecting therefrom;and an elongated housing disposed approximately parallel with thelongitudinal axis of said engine, said housing enclosing such of saidparts as lie beyond said cowl, the inner side of said housing abuttingsaid cowl and closing the opening therein, and ribs extending from saidhead to said housing, said housing being integral with said head andsaid ribs integral with both said head and housing, whereby heattransference between said head and housing is accomplished.

2. In an aircraft, an engine having a plurality of radial cylinders, acowl concentric with the longitudinal axis of said engine encirclingsaid engine, said cowl being apertured at each cylinder. and the headsof the cylinders extending through said apertures; each cylinder headcarrying projecting parts including valve stems valve passageways andactuating means coacting with said valve stems; an elongated housingdisposed with its length substantially parallel to said axis enclosingsuch of said parts and head as project beyond said cowl, the inner sideof said housing abutting said cowl, and closing the aperture therein,said housing being integral with said head for heat transfer therefrom.

3. In an aircraft, an engine having a plurality of radial cylinders, anannular exhaust ring disposed forwardly of said cylinders and concentricwith the longitudinal axis of the engine, a cowl concentric with saidaxis forming a rearward continuation of the outer surface of said ringand enclosing said engine, said cowl being apertured at each cylinder,and the heads of the cylinders extending through said apertures; eachcylinder head carrying projecting parts, an elongated housing, disposedwith its length parallel tosaid axis, enclosing such of said parts andhead, as he beyond said cowl, the inner side of said housing abuttingsaid cowl and closing the opening therein, and ribs extending from headto said housing, said housing, head and ribs being integral for transferof heat from said head to said housing, and said housing being streamlined whereby air may flow smoothly past said housing for removal ofheat therefrom.

4. In an aircraft, an engine having a plurality of radial cylinders, anannular exhaust ring disposed forwardly of said cylinders, andconcentric with the longitudinal axis of said engine, a cowl concentricwith said axis, forming a rearward continuation of the outer surface ofsaid ring and enclosing said engine, said cowl being apertured at eachcylinder and the heads of the cylinders extending through saidapertures; each cylinder head carrying projecting parts includingexhaust and intake passageways; an elongated housing, disposed with itslength approximately parallel to said axis, enclosing such of said partsand head as lie beyond said cowl, the inner side of said housingabutting said cowl and closing the opening therein, said housing andhead being integral for heat transference, said intake passagewayleading rearwardly from said head within said housing and inward throughsaid cowl opening, said exhaust passageway leading forwardly through thefront of said housing and inward to a junction with said exhaust ring,said exhaust passageway and housing being streamlined to present aminimum of air resistance.

5. In an air cooled combustion engine, a cylinder head, valves in saidhead, actuating means for said valves, passageways leading from saidvalves, heat conducting means for said head integral therewith, and anelongated hollow divided housing enclosing the exposed part of saidhead, valves, actuating means, passageways and conducting means, onepart of said divided housing being integral with said head and with saidconducting means.

6. An air cooled aircraft engine having a cylinder with a head, metallicheat transference means for said head integral therewith, an elongatedhollow housing covering said head and heat transference means, and acowl for said engine, a portion of said head extending outside thesurface lines of said cowl and into said housing.

'7. An air cooled aircraft engine cylinder having a head, projectingparts carried thereby including valve stems and actuating means for saidvalve stems, and passageways leading from the valves; an elongatedhollow housing enclosing said head and parts and cooling fins on saidhead connecting said head with said housing.

8. An air cooled aircraft engine provided with a cylinder and a headtherefor, and mounted within a cowl having an opening therein beyondwhich said head projects; a housing extending over said head andsubstantially over said opening, and heat-transference means betweensaid head and said housing.

9. An air cooled aircraft engine provided with a cylinder and a headtherefor, and mounted within a cowl having an opening therein beyondwhich said head projects; said head being provided with inlet andexhaust passages extending in a direction substantially parallel withthe longitudinal axis of said cowl, a housing elon gated to extend overboth of said passages and close said opening, and cooling means betweensaid head and said housing.

10. An air cooled aircraft engine provided with a cylinder and a headtherefor, and mounted within a streamlined cowl having an openingtherein beyond which said head projects; a housing extending over saidhead and closing said opening, and streamlined in conformity with thestreamlining of said cowl, and cooling means between said head and saidhousing.

11. An air cooled aircraft engine provided with a cylinder and a headtherefor, and mounted within a cowl having an opening therein beyondwhich said head projects; said head carrying valves and operating meanstherefor, a housing extending over said valves and operating meanspassage communicating with the interior of said cylinder, a valve insaid passagaand operating .means for said valve, a housing extendingover said passage and said parts and closing said cowl opening, andcooling means between said head and said housing.

13. An aircooled aircraft engine provided with a cylinder and 'a headtherefor, and mounted within a cowl having an opening therein beyondwhich said head projects; a housing extending over said head, closingsaid opening, and being secured to said cowl, and heat-transferencemeans between said head and said housing.

14. An air cooled aircraft engine provided with a cylinder and a headtherefor, and mounted within a cowl having an opening therein beyondwhich said head projects; a housing extending over said head, andclosing and sealing said opening, and heat-transference means betweensaid head and said housing.

15. An air cooled aircraft engine having a cylinder and a head therefor,a streamlined housing for said head, an inlet passage, an exhaustpassage a wall of which forms part of said housing, said exhaust passagebeing at the diverging air impingement side of said housing, whereby itreceives maximum cooling effect from the streamline air, andheat-transference means between said head and said housing.

16. An air cooled aircraft engine having a cylinder and a head therefor,a stream lined housing for said head, an inlet passage, an exhaustpassage a wall of which forms part of said housing, said exhaust passagebeing at the diverging air-impingement side of said housing, and saidinlet passage being at the opposite side thereof, whereby said exhaustpassage is subjected to greater cooling effect from the stream line airthan is said inlet passage, and heat transference means between saidhead and said housing.

17. An air cooled aircraft engine having a cylinder and a head therefor,a housing for said head having an inlet passage and an exhaust passagerespectively located at different sides of said head, said housing beingelongated to cover and form a wall of said exhaust passage, and beingstreamlined first to diverge and then to converge from said exhaustpassage toward said inlet passage, and heat-transference means betweensaid head and said housing.

18. In an air-cooled, internal-combustion engine, a cylinder head, aninlet valve and an outlet valve therein, each having a protruding stem,actuating parts for said valves carried by and exterior to said head,and a streamlined hollow housing of convex external configuration,enclosing and protecting both of said valves and said actuating parts, aportion of said housing remote from said head being removably secured topermit access to the interior thereof.

19. An air-cooled, internal-combustion-engine cylinder head, having aninlet valve, an exhaust valve, and valve-actuating mechanism, allcarried thereby, and an elongated housing covering and protecting saidparts, and stream-lined to converge from its major portion toward saidinlet valve.

20. In an air-cooled, internal-combustion engine, a cylinder head havingan inlet port and 1 an exhaust port, and valves therefor, and anelongated housing enclosing said head and said valves, and extended toform a Wall of a passage-way leading from said exhaust port.

'21, In an air-cooled, internal-combustion engine, a cylinder headhaving an inlet port and an exhaust port, and valves therefor, and anelongated housing enclosing said head and said ports, and stream-linedto converge from its major portion toward said exhaust valve.

22. In an air-cooled, internal-combustion engine, a cylinder head havingan inlet port and an exhaust port, and valves therefor, and an elongatedhousing enclosing said. head and said means for said head integraltherewith, and an elongated housing enclosing said valves, saidactuating means and said cooling means, and constituting a Wall of saidexhaust passageway.

HARRY L. MCPHERSON.

